you can talk about the u.s. and iran going at it, but as always, it's the everyday citizens caught in the middle. that story does a great job of pointing out just how it impacts everyday life. just the basics like medicine. >> you hear about sanctions and it doesn't mean anything until you see a story like this. >> there's policy, and there's real tif and policy's impact on that. >>> and getting through. how science teachers are turning to popular music. how this class act is helping students finally take interest. >> i wish i had this earlier in the week. whatever it takes. however you get the message across, the fact that it gets across is a good thing. >>> but first, leading once again with weather. a monster of a storm is dumping snow in the middle of the country and spawning killer tornadoes. >> hemphill, texas area was hit hard. and it's far from over, as severe weather warnings are up across a big section of the country this morning. our coverage begins with abc's brad wheelis. >> reporter: old man winter